There are lots of embedded solutions around, but not a lot that sell to consumers. The Soekris units will easily fit in a 1U shelf and two of ’em would make a really good n’ cheap LVS load balancing/HA solution. At $250 a pop, it’s a few thousand cheaper than buying hardware load balancing, even if you’re getting it used.

• Soekris Engineering – relatively cheap, designed for embedded applications (486/133, so you’d probably want the security accelerator if you’re building a vpn
• Hacom OpenBrick
• NEXCOM EBS 1563

Related: LEAF, m0n0wall, JFFS : The Journalling Flash File System